Pjrek E, Friedrich ME, Cambioli L, et al. - In this meta-analysis, researchers investigated whether bright light therapy (BLT) is efficacious in the treatment of the seasonal affective disorder (SAD) in adults. Nineteen studies were identified for inclusion in the analysis. Evidence gained suggested the superiority of BLT over placebo with a standardized mean difference of –0.37 (95% CI: –0.63 to –0.12) for depression ratings (18 studies, 610 patients) and a risk ratio of 1.42 (95% CI: 1.08–1.85) for response to active treatment (16 studies, 559 patients). Findings thereby provide a possible value of BLT as an effective treatment for SAD. However, evidence gained stems from moderately heterogeneous studies with a moderate-to-high risk of bias.